[Question] Locking Advantages

You see a Wight Dwarf heading towards you...
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-From our Bazaar of the Bizarre campaign-

Another problem child of mine came to me with a locked lycanthrope[ish] character idea.

Right now the situation is:

[BF] Base Form [Human]
[AF-A] Alternate Form A [Wolf-Man]
[AF-Z] Alternate From Z [Wolf]

To get from [BF] to [AF-Z] you must pass through [AF-A], the reverse is also true - to get from [AF-Z] to [BF] you must pass through [AF-A].

[BF]<---------->[AF-A]<---------->[AF-Z]

That part is simple - I just told him to slapp [Required Intermediate Form, -10%] from GURPS Fantasy onto [AF-Z].

I need help figuring out the [Limitation] to use to show that the other forms are inaccessible until the [Limitation] is bought off.

Basically [AF-Z] has temporarily become the only available form, at least until the penalty is paid off, or the group works around the problem and restores the character's ability to shift back.

So there is a lock/block between [AF-Z] and [AF-A] and one between [AF-A] and [BF].

[AF-Z]<-----|X|----->[AF-A]<-----|X|----->[BF]

They'll have to unlock/unblock [AF-A] before unlocking [BF].


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Werewolf, Werewolf..... There Wolf, There Wolf!!!

[Question] Locking Advantages